Forrester interviewed four large VMware customers in financial services, manufacturing, and high-tech that run hundreds of virtual machines. We wanted to find out what they'd learned about managing large production VMware environments and how they've dealt with the top questions we get from other clients about server virtualization. Aside from consolidation savings, the most notable effect has been ease of management. While many potential customers are concerned about adding complexity, each of these customers has found that virtualization simplifies their administrators' lives — particularly when provisioning new systems.